The Department of Veterans Affairs (VA) recognizes three types of disclosure of adverse events: 1) clinical disclosure, 2) institutional disclosure and 3) large scale disclosure. Decision regarding notification of large scale adverse events, defined as involving three or more patients, are made by the Principal Deputy Under Secretary of Health (PDUSH) in consultation with the Clinical Review Board (CRB) following guidelines based on probability of exposure and severity of the event on Veterans' health outcomes. Large scale adverse event communication is unique in that many Veterans are potentially exposed but few are truly at risk of infectious disease. Working with our operational partners-Office of the PDUSH, Office of Public Health (10P3), HIV/Hepatitis QUERI and the Health Economics Resource Center (HERC)--we have developed key research questions which reflect VHA leadership concerns when making decisions to notify Veteran patients of potential risks of infection following infection control breaches. We will employ a conceptual model of Crisis and Emergency Risk Communication model to identify optimal, patient-centered communication strategies to minimize risk of harm and unintended consequences following large scale disclosure over several communication time points: (1) initial communication; (2) maintenance communication; (3) resolution communication and (4) follow-up /evaluative communication. Our current work on clinical disclosures shows that ideal communication occurs over several time points and serves different purposes at each time. Our four staged studies involving qualitative and quantitative methodologies will address three key short-term objectives in this Service Directed Research proposal: (1) To explore the effect of VA large scale adverse events on Veterans', their families', and VHA staff perceptions of VA services, risk to self, and emotional responses to notification; (2) To determine the impact of past VA notification procedures on unintended outcomes, such as Veterans' and VHA staff anxiety and distress, Veterans' trust in the VA, self-efficacy for action, perceptions of risk of harm, and changes and cost in VA healthcare utilizations; (3) To empirically test the effectiveness of different models of notification procedures and language based on evidence collected in the SDR on Veterans' trust in the VA, anxiety and distress, self-efficacy for action, perceptions of risk of harm and decreased or increased cost and utilization. Our long-term objective is to develop a large scale adverse event notification tool kit that can be distributed b the PDUSH, CRB and our 10P3 partners to VHA and medical center leadership for use when notifying Veterans of possible risk of infection following large scale adverse events that occurred in VHA facilities where they received care. Study 1 will involve a content analysis of media reports and past notification letters to inform media and communication strategies in future disclosures. Study 2 involves interviews with Veterans, their families, VHA staff and leadership at the six VHA facilities who have disclosed large scale adverse events in the past two years. These interviews will benefit from the experiences of users of the VHA system, their families, and the staff affected most by the adverse event and disclosure process, to understand more about what worked and what needs to be improved in future strategies. Study 3 will examine the unintended consequences of adverse event notification by analyzing VA and Medicare cost and health care utilization data sets. We will seek to understand whether Veterans stayed in the VHA system following disclosure, whether they sought care outside the VA, whether costs decreased or increased, and the time it took for any changes to return to baseline. Study 4 will build on the previous three studies by creating large scale disclosure vignettes depicting different infection risk levels (high vs. low), and different types of large scale adverse events (dental vs. colonoscopy) which will vary by the notification medium (phone call, letter or both from VHA facilities). We will experimentally manipulate these variables to determine the optimal responses to questions about perceptions of risk of harm, trust in VA, self-efficacy for action and distress levels. These findings will culminate in the development of a large scale adverse event tool kit for wide distribution through the Principal Deputy Under Secretary for Health and the Office of Public Health. A future prospective study is proposed to evaluate the dissemination and implementation of the tool kit during an actual large scale adverse event disclosure process.